This is not like the Google related or similar pages where you start with a single relevant page and ask Google to find other pages similar in type and content. The Gigablast offering works at the search level: you type in your search strategy as usual and near the top of the results list there is a “related” pages section displaying a few extra pages with a more link to other “related” pages.
I found that they do not always appear, especially when you type in a complex or more detailed strategy. Also, I am a bit suspicious as to how these so called related pages are selected. Gigablast gives an example of searching on Colorado activities:
“You will see many webpages which are contextually related to the original query terms, but have no obvious direct connection to them. Many show the word Colorado, but not activities or activity, yet the pages all seem to fit well into the descriptive two-word query Colorado activities.”
And then:
“Upon searching for the original query terms within several of these pages, one is left wondering how the Gigablast software code is able to distinguish them as being relevant in the first place. The answers? …proprietary, of course.”
After running a few of my standard test searches, I have the impression that a lot of these pages could be paid-for placements and not many were relevant to my searches. But perhaps I am being uncharitable. More useful to me is the Giga Bits section, which shows alternative search strategies and they are relevant.